A solid-state image sensing device having a plurality of photodiodes serving as photoelectric conversion portions for incident light and a MOS (Metal Oxide Semiconductor) transistor serving as an insulating gate field effect transistor portion is disclosed, for example, in Japanese Patent Laying-Open No. 2004-228425, Japanese Patent Laying-Open No. 2008-041958, and the like.
Japanese Patent Laying-Open No. 2004-228425 above describes simultaneous formation of an antireflection coating for a photodiode and a sidewall along the side of a gate of a MOS transistor for decreasing the number of steps and simplification of the steps.
Japanese Patent Laying-Open No. 2008-041958, however, describes the fact that a thickness of the antireflection coating and a thickness of the sidewall cannot independently be controlled with the manufacturing method in Japanese Patent Laying-Open No. 2004-228425.
In this Japanese Patent Laying-Open No. 2008-041958, an antireflection coating and a sidewall are formed in the same step from an insulating film including three layers of a lower layer, an intermediate layer and an upper layer. According to this publication, an index of refraction and a thickness of the antireflection coating are controlled by the two layers of the lower and inteunediate insulating films and a thickness of the sidewall is controlled by the three layers of the lower layer, the intermediate layer and the upper layer, so that each thickness of the antireflection coating and the sidewall can independently be controlled.